The present invention relates to a method and apparatus for turning stackable cups to a stackable position, especially to comparatively shallow cups, the height of which is less than the greatest diameter of the cup at the open end, which is wider in relation to the bottom end. With the type of cups which is primarily intended, the height of the cup lies within the range of about one half to about three quarters of said greatest diameter.
The cups in question may be made with or without a handle.
In the manufacture of plastic cups by injection moulding, the completed cups are fed onto a collecting table, where most of the cups assume one of the main positions: resting on the bottom end, resting on the open end or lying on one side. Further positions can occur, where for example two cups lie on top of each other, or when the cups are provided with handles, are connected together by the handle of one cup lying for example under the edge of another cup. In the case where the cups are not made with handles there is a known method for righting the cups by guiding them in between two conveyor belts on edge and having a distance between their upper edges less than the overall diameter of the cup, causing the cups to be suspended at the edges of the belts. At the further end of the belts, the righted cups are fed to a stacking device. However, this known method is not suitable for cups provided with handles. Such cups provided with handles must therefore be picked manually from the collecting table and stacked into each other by hand to a stack having the desired number of cups, which normally requires the work of two people.